Field Behavior of an Integral Abutment Bridge Supported on Drilled Shafts
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Introduction to Artificial Intelligence智慧树知到课后章节答案2023年下哈尔滨工程大学哈尔滨工程大学第一章测试1.All life has intelligence The following statements about intelligence arewrong()A:All life has intelligence B:Bacteria do not have intelligence C:At present,human intelligence is the highest level of nature D:From the perspective of life, intelligence is the basic ability of life to adapt to the natural world答案:Bacteria do not have intelligence2.Which of the following techniques is unsupervised learning in artificialintelligence?()A:Neural network B:Support vector machine C:Decision tree D:Clustering答案:Clustering3.To which period can the history of the development of artificial intelligencebe traced back?()A:1970s B:Late 19th century C:Early 21st century D:1950s答案:Late 19th century4.Which of the following fields does not belong to the scope of artificialintelligence application?()A:Aviation B:Medical C:Agriculture D:Finance答案:Aviation5.The first artificial neuron model in human history was the MP model,proposed by Hebb.()A:对 B:错答案:错6.Big data will bring considerable value in government public services, medicalservices, retail, manufacturing, and personal location services. ()A:错 B:对答案:对第二章测试1.Which of the following options is not human reason:()A:Value rationality B:Intellectual rationality C:Methodological rationalityD:Cognitive rationality答案:Intellectual rationality2.When did life begin? ()A:Between 10 billion and 4.5 billion years B:Between 13.8 billion years and10 billion years C:Between 4.5 billion and 3.5 billion years D:Before 13.8billion years答案:Between 4.5 billion and 3.5 billion years3.Which of the following statements is true regarding the philosophicalthinking about artificial intelligence?()A:Philosophical thinking has hindered the progress of artificial intelligence.B:Philosophical thinking has contributed to the development of artificialintelligence. C:Philosophical thinking is only concerned with the ethicalimplications of artificial intelligence. D:Philosophical thinking has no impact on the development of artificial intelligence.答案:Philosophical thinking has contributed to the development ofartificial intelligence.4.What is the rational nature of artificial intelligence?()A:The ability to communicate effectively with humans. B:The ability to feel emotions and express creativity. C:The ability to reason and make logicaldeductions. D:The ability to learn from experience and adapt to newsituations.答案:The ability to reason and make logical deductions.5.Which of the following statements is true regarding the rational nature ofartificial intelligence?()A:The rational nature of artificial intelligence includes emotional intelligence.B:The rational nature of artificial intelligence is limited to logical reasoning.C:The rational nature of artificial intelligence is not important for itsdevelopment. D:The rational nature of artificial intelligence is only concerned with mathematical calculations.答案:The rational nature of artificial intelligence is limited to logicalreasoning.6.Connectionism believes that the basic element of human thinking is symbol,not neuron; Human's cognitive process is a self-organization process ofsymbol operation rather than weight. ()A:对 B:错答案:错第三章测试1.The brain of all organisms can be divided into three primitive parts:forebrain, midbrain and hindbrain. Specifically, the human brain is composed of brainstem, cerebellum and brain (forebrain). ()A:错 B:对答案:对2.The neural connections in the brain are chaotic. ()A:对 B:错答案:错3.The following statement about the left and right half of the brain and itsfunction is wrong ().A:When dictating questions, the left brain is responsible for logical thinking,and the right brain is responsible for language description. B:The left brain is like a scientist, good at abstract thinking and complex calculation, but lacking rich emotion. C:The right brain is like an artist, creative in music, art andother artistic activities, and rich in emotion D:The left and right hemispheres of the brain have the same shape, but their functions are quite different. They are generally called the left brain and the right brain respectively.答案:When dictating questions, the left brain is responsible for logicalthinking, and the right brain is responsible for language description.4.What is the basic unit of the nervous system?()A:Neuron B:Gene C:Atom D:Molecule答案:Neuron5.What is the role of the prefrontal cortex in cognitive functions?()A:It is responsible for sensory processing. B:It is involved in emotionalprocessing. C:It is responsible for higher-level cognitive functions. D:It isinvolved in motor control.答案:It is responsible for higher-level cognitive functions.6.What is the definition of intelligence?()A:The ability to communicate effectively. B:The ability to perform physicaltasks. C:The ability to acquire and apply knowledge and skills. D:The abilityto regulate emotions.答案:The ability to acquire and apply knowledge and skills.第四章测试1.The forward propagation neural network is based on the mathematicalmodel of neurons and is composed of neurons connected together by specific connection methods. Different artificial neural networks generally havedifferent structures, but the basis is still the mathematical model of neurons.()A:对 B:错答案:对2.In the perceptron, the weights are adjusted by learning so that the networkcan get the desired output for any input. ()A:对 B:错答案:对3.Convolution neural network is a feedforward neural network, which hasmany advantages and has excellent performance for large image processing.Among the following options, the advantage of convolution neural network is().A:Implicit learning avoids explicit feature extraction B:Weight sharingC:Translation invariance D:Strong robustness答案:Implicit learning avoids explicit feature extraction;Weightsharing;Strong robustness4.In a feedforward neural network, information travels in which direction?()A:Forward B:Both A and B C:None of the above D:Backward答案:Forward5.What is the main feature of a convolutional neural network?()A:They are used for speech recognition. B:They are used for natural languageprocessing. C:They are used for reinforcement learning. D:They are used forimage recognition.答案:They are used for image recognition.6.Which of the following is a characteristic of deep neural networks?()A:They require less training data than shallow neural networks. B:They havefewer hidden layers than shallow neural networks. C:They have loweraccuracy than shallow neural networks. D:They are more computationallyexpensive than shallow neural networks.答案:They are more computationally expensive than shallow neuralnetworks.第五章测试1.Machine learning refers to how the computer simulates or realizes humanlearning behavior to obtain new knowledge or skills, and reorganizes the existing knowledge structure to continuously improve its own performance.()A:对 B:错答案:对2.The best decision sequence of Markov decision process is solved by Bellmanequation, and the value of each state is determined not only by the current state but also by the later state.()A:对 B:错答案:对3.Alex Net's contributions to this work include: ().A:Use GPUNVIDIAGTX580 to reduce the training time B:Use the modified linear unit (Re LU) as the nonlinear activation function C:Cover the larger pool to avoid the average effect of average pool D:Use the Dropouttechnology to selectively ignore the single neuron during training to avoid over-fitting the model答案:Use GPUNVIDIAGTX580 to reduce the training time;Use themodified linear unit (Re LU) as the nonlinear activation function;Cover the larger pool to avoid the average effect of average pool;Use theDropout technology to selectively ignore the single neuron duringtraining to avoid over-fitting the model4.In supervised learning, what is the role of the labeled data?()A:To evaluate the model B:To train the model C:None of the above D:To test the model答案:To train the model5.In reinforcement learning, what is the goal of the agent?()A:To identify patterns in input data B:To minimize the error between thepredicted and actual output C:To maximize the reward obtained from theenvironment D:To classify input data into different categories答案:To maximize the reward obtained from the environment6.Which of the following is a characteristic of transfer learning?()A:It can only be used for supervised learning tasks B:It requires a largeamount of labeled data C:It involves transferring knowledge from onedomain to another D:It is only applicable to small-scale problems答案:It involves transferring knowledge from one domain to another第六章测试1.Image segmentation is the technology and process of dividing an image intoseveral specific regions with unique properties and proposing objects ofinterest. In the following statement about image segmentation algorithm, the error is ().A:Region growth method is to complete the segmentation by calculating the mean vector of the offset. B:Watershed algorithm, MeanShift segmentation,region growth and Ostu threshold segmentation can complete imagesegmentation. C:Watershed algorithm is often used to segment the objectsconnected in the image. D:Otsu threshold segmentation, also known as themaximum between-class difference method, realizes the automatic selection of global threshold T by counting the histogram characteristics of the entire image答案:Region growth method is to complete the segmentation bycalculating the mean vector of the offset.2.Camera calibration is a key step when using machine vision to measureobjects. Its calibration accuracy will directly affect the measurementaccuracy. Among them, camera calibration generally involves the mutualconversion of object point coordinates in several coordinate systems. So,what coordinate systems do you mean by "several coordinate systems" here?()A:Image coordinate system B:Image plane coordinate system C:Cameracoordinate system D:World coordinate system答案:Image coordinate system;Image plane coordinate system;Camera coordinate system;World coordinate systemmonly used digital image filtering methods:().A:bilateral filtering B:median filter C:mean filtering D:Gaussian filter答案:bilateral filtering;median filter;mean filtering;Gaussian filter4.Application areas of digital image processing include:()A:Industrial inspection B:Biomedical Science C:Scenario simulation D:remote sensing答案:Industrial inspection;Biomedical Science5.Image segmentation is the technology and process of dividing an image intoseveral specific regions with unique properties and proposing objects ofinterest. In the following statement about image segmentation algorithm, the error is ( ).A:Otsu threshold segmentation, also known as the maximum between-class difference method, realizes the automatic selection of global threshold T by counting the histogram characteristics of the entire imageB: Watershed algorithm is often used to segment the objects connected in the image. C:Region growth method is to complete the segmentation bycalculating the mean vector of the offset. D:Watershed algorithm, MeanShift segmentation, region growth and Ostu threshold segmentation can complete image segmentation.答案:Region growth method is to complete the segmentation bycalculating the mean vector of the offset.第七章测试1.Blind search can be applied to many different search problems, but it has notbeen widely used due to its low efficiency.()A:错 B:对答案:对2.Which of the following search methods uses a FIFO queue ().A:width-first search B:random search C:depth-first search D:generation-test method答案:width-first search3.What causes the complexity of the semantic network ().A:There is no recognized formal representation system B:The quantifiernetwork is inadequate C:The means of knowledge representation are diverse D:The relationship between nodes can be linear, nonlinear, or even recursive 答案:The means of knowledge representation are diverse;Therelationship between nodes can be linear, nonlinear, or even recursive4.In the knowledge graph taking Leonardo da Vinci as an example, the entity ofthe character represents a node, and the relationship between the artist and the character represents an edge. Search is the process of finding the actionsequence of an intelligent system.()A:对 B:错答案:对5.Which of the following statements about common methods of path search iswrong()A:When using the artificial potential field method, when there are someobstacles in any distance around the target point, it is easy to cause the path to be unreachable B:The A* algorithm occupies too much memory during the search, the search efficiency is reduced, and the optimal result cannot beguaranteed C:The artificial potential field method can quickly search for acollision-free path with strong flexibility D:A* algorithm can solve theshortest path of state space search答案:When using the artificial potential field method, when there aresome obstacles in any distance around the target point, it is easy tocause the path to be unreachable第八章测试1.The language, spoken language, written language, sign language and Pythonlanguage of human communication are all natural languages.()A:对 B:错答案:错2.The following statement about machine translation is wrong ().A:The analysis stage of machine translation is mainly lexical analysis andpragmatic analysis B:The essence of machine translation is the discovery and application of bilingual translation laws. C:The four stages of machinetranslation are retrieval, analysis, conversion and generation. D:At present,natural language machine translation generally takes sentences as thetranslation unit.答案:The analysis stage of machine translation is mainly lexical analysis and pragmatic analysis3.Which of the following fields does machine translation belong to? ()A:Expert system B:Machine learning C:Human sensory simulation D:Natural language system答案:Natural language system4.The following statements about language are wrong: ()。
there is consensus in the field ofsecond languageThere is consensus in the field of second language acquisition that learners' motivation and attitude towards the target language play a crucial role in their learning process. Motivation can be intrinsic, extrinsic, or a combination of both. Intrinsic motivation comes from the learner's personal interest and desire to learn the language, while extrinsic motivation is driven by external factors such as grades, career opportunities, or social pressure. A positive attitude towards the target language and its speakers can also enhance learners' motivation and engagement.Another important factor that has gained consensus in the field is the influence of the learners' first language (L1) on their second language (L2) acquisition. The L1 can have both positive and negative effects on L2 learning. On the one hand, the L1 can provide a transfer of language knowledge and strategies that can facilitate L2 learning. For example, similarities between the L1 and L2 in terms of vocabulary, grammar, or pronunciation can help learners to make connections and accelerate their learning. On the other hand, the L1 can also interfere with L2 learning if learners rely too much on L1 patterns andAttempt to translate every word or phrase from L2 to L1.In addition, there is a consensus that interaction and exposure to the target language are essential for second language acquisition. Meaningful communication with native speakers or other L2 learners, as well as exposure to authentic language input through various media, can enhance learners' language proficiency and cultural awareness. Immersion in a language environment and opportunities for practice and feedback are also considered important for effective language learning.Furthermore, the role of individual learner differences, such as age, learning style, and cognitive abilities, has been acknowledged in the field. Research has shown that younger learners may have an advantage in acquiring certain aspects ofa second language, while adult learners may bring more metalinguistic awareness and learning strategies to the process. Understanding and accommodating individual learner differences can help educators and learners tailor their learning experiences and approaches.In conclusion, the field of second language acquisition recognizes the importance of motivation, the influence of the first language, interaction and exposure, and individual learner differences in the learning process. These factors collectively contribute to the successful acquisition of a second language.。
高中英语学术论文研究方法练习题40题1.Which of the following topics is most suitable for a high school English academic paper?A.The history of video games.B.The influence of social media on teenagers' language learning.C.The development of artificial intelligence in the medical field.D.The architecture of ancient Rome.答案:B。
解析:选项 A 视频游戏历史与高中英语学术论文关联不大。
选项C 人工智能在医疗领域的发展与英语学科不相关。
选项D 古罗马建筑也与英语学科没有直接关系。
而选项B 社交媒体对青少年语言学习的影响既与英语语言相关,也适合高中学生进行研究。
2.In choosing a topic for an English academic paper, what should be considered first?A.Personal interest.B.Availability of resources.C.Relevance to the curriculum.D.Popularity of the topic.答案:C。
解析:选项 A 个人兴趣虽然重要,但不是首先要考虑的。
选项 B 资源的可获得性在确定选题后再考虑。
选项 D 话题的流行度不是关键因素。
首先应考虑与课程的相关性,这样才能确保论文在学科范围内有意义。
3.Which of the following is NOT a good criterion for choosing anacademic paper topic?A.Being too broad.B.Having enough research materials available.C.Being relevant to current events.D.Being easy to research.答案:A。
2024年成人高考成考英语(高起专)复习试卷及解答参考一、语音知识(本大题有5小题,每小题2分,共10分)1、Choose the word that has the same pronunciation as the word “elephant.”A. elephantB. elephantC. elephantD. elephantAnswer: BExplanation: The word “elephant” is pronounced as /ˈɛl.ɪ.fɑːnt/. Among the options provided, “elephant” in option B is pronounced the same as the original word.2、Select the word that has the opposite meaning of “increase.”A. increaseB. increaseC. decreaseD. decreaseAnswer: CExplana tion: The word “increase” means to make larger or greater. The wordthat has the opposite meaning is “decrease,” which means to make smaller or less. Among the options, “decrease” in option C is the correct answer.3、The word “communicate” is pronounced as:A. /kəˈmjuːnɪkeɪt/B. /kəˈmjuːnɪkeɪt/C. /kəˈmjuːniːkeɪt/D. /kəˈmjuːniːkeɪt/Answer: AExplanation: The correct pronunciation of “communicate” is /kəˈmjuːnɪkeɪt/. The “c” in “communicate” is not hard, as it does not precede a double vowel.4、Which of the following words has the correct pronunciation?A. “Environment” - /ɪnˌvaɪrənˈmeɪnt/B. “Education” - /ˌɛdʒuˈkeɪʃən/C. “Imagine” - /ɪˈmædʒɪneɪt/D. “Compass” - /kəˈmæpəs/Answer: BExplanation: The correct pronunciation of “education” is /ˌɛdʒuˈkeɪʃən/. The “e” in “education” is long, as it is followed by a “g” which is silent. The other options have mispronounced vowels or consonants.5、The sentence “She always has a smile on her face” emphasizes that sheis always __________.A. cheerfulC. nervousD. sadAnswer: A. cheerfulExplanation: The word “always” in the sentence indicates a constant state or behavior. The phrase “has a smile on her face” suggests that she is in a good mood or happy, which is best described by the word “cheerful.” The other options do not accurately capture the positive connotation of the sentence.二、词汇与语法知识(本大题有15小题,每小题2分,共30分)1、Choose the correct word or phrase to complete the sentence below.The_______of the meeting was quite impressive.A. atmosphereB. audienceC. attendanceD. occasionAnswer: CExplanation: The correct answer is “attendance” because it refers to the number of people who were present at the meeting. The other options do not fit the context of the sentence.2、Select the word that does not belong in the following list.A. enthusiasticC. exhaustedD. alertAnswer: CExplanation: The word “exhausted” does not belong in the list because it is an adjective that describes someone who is very tired, whereas “enthusiastic,” “energetic,” and “alert” all describe someone who is full of energy or has a positive, watchful attitude.3、Choose the word that best completes the sentence.The teacher___________the students to be quiet during the examination.A. requestedB. suggestedC. orderedD. recommendedAnswer: C. orderedExplanation: The correct choice is “ordered” because it indicates a direct command or instruction from the teacher. The other options, while they could be used in some contexts, do not convey the same level of authority or necessity as “ordered” does in this sentence.4、Complete the sentence using the correct form of the verb in parentheses.If you________(be) more careful, you would not have made so many mistakes.A. areB. wereC. will beD. had beenAnswer: B. wereExplanation: The correct form of the verb to use in this sentence is “were,” which i s the past subjunctive form of “to be.” The sentence is expressing a hypothetical situation, which is a situation that is not real but is being considered for the sake of argument. The past subjunctive is used to describea condition that is not true but could have been or would have been.5、Choose the word that best completes the sentence.The professor___________the students’ questions eagerly.A. ignoredB. addressedC. neglectedD. overlookedAnswer: B. addressedExplanation: The correct word to complet e the sentence is “addressed,” which means to speak to or write to someone formally or officially. The professor is expected to address the students’ questions, not ignore, neglect, or overlook them.6、Complete the sentence with the correct form of the verb in parentheses.They___________(be) discussing the project when the meeting was called toorder.A. wereB. had beenC. have beenD. isAnswer: A. wereExplanation: The correct form of the verb is “were,” which is the past continuous tense. The sentence describes an action that was happening at a specific past time (when the meeting was called to order), so the past continuous tense is appropriate. The other options are incorrect because they do not match the context or the tense required.7、Choose the word that best completes the sentence.The teacher was surprised by the student’s_ability to understand complex concepts.A)surpriseB)surprisedC)surprisingD)surpriseablyAnswer: C) surprisingExplanation: The correct answer is “surprising” because it is the adjective form that describes the student’s ability. “Surprise” is a noun, “surprised” is the past participle form of the verb, and “surpriseably” is not a word.8、Complete the sentence with the correct form of the given verb in brackets.They (be) (not) aware of the changes that (take) place in the company last month.A)wereB)areC)wasD)beAnswer: A) wereExplanation: The correct answer is “were” because the subject “they” is plural, and the past perfect tense “had taken” indicates that the cha nges occurred before the awareness of them. Therefore, “were” is the correct past tense form of “be.”9.Choose the word that best completes the sentence.I can’t believe how____________changes have occurred in this small town over the past decade.A)numerousB)rapidC)suddenD)gradualAnswer: D) gradualExplanation: The sentence is describing changes that have occurred over a period of time, suggesting a process that was not immediate or extreme. “Gradual” fits this context best, indicating changes that happen slowly over time.10.Select the correct form of the verb to complete the following sentence.The professor___________us a detailed outline of the research project before the deadline.A)gaveB)has givenC)will giveD)is givingAnswer: B) has givenExplanation: The sentence implies that the action of giving the outline has already occurred before the deadline. The present perfect tense (“has given”) is used to describe actions that have a present relevance or result.11.Choose the correct word to complete the sentence:The manager was_about the new project, but the team was confident.A)apprehensiveB)optimisticC)indifferentD)enthusiasticAnswer: A) apprehensiveExplanation: The correct answer is “apprehensive” because it means feeling or showing anxiety or fear about something, which fits the context of the manager being concerned about the new project. The other options do not convey the same sense of worry or anxiety.12.Select the word that is closest in meaning to the underlined word:The teacher’s_appr oach to teaching made the subject much more engaging.A)traditionalB)innovativeC)passiveD)objectiveAnswer: B) innovativeExplanation: The underlined word “innovative” means introducing new methods or ideas. The sentence suggests that the teacher’s approach was different and made the subject more engaging. The word “traditional” would imply a more conventional method, “passive” would suggest a lack of interest, and “objective” would imply a neutral approach, none of which fit the context as well as “innovative.”13.Choose the word that best completes the sentence.The company’s new policy has been widely __________, with both positive and negative reactions.A. criticizedB. implementedC. supportedD. rejectedAnswer: B. implementedExplanation: The correct word here should reflect that the policy has been put into effect. “Implemented” means to carry out or put into effect, which fits the context. “Criticized” would imply there are negative reactions,“supported” would imply positive reactions, and “rejected” wo uld imply outright refusal, none of which fully capture the act of the policy being put into practice.14.Select the correct form of the verb to complete the sentence.She_______(go) to the market every morning, but now she has a car.A. used to goB. uses to goC. used goD. uses goAnswer: A. used to goExplanation: The correct phrase to use in this context is “used to” followed by the base form of the verb, which indicates a past habit or practice that has since changed. “Used to go” is the correc t past simple form that indicates a habit in the past. The other options are grammatically incorrect or do not convey the intended meaning.15.Choose the correct word or phrase to complete the sentence.The professor___________the students to study hard for the exam.A. advisedB. recommendedC. suggestedD. proposedAnswer: B. recommendedExplanation: The correct answer is “recommended” because it is the most appropriate word to express the professor’s advice. “Advised,” “suggested,” and “proposed” can also mean giving advice or suggestions, but “recommended”is often used in a more formal context, such as in an academic setting.三、完形填空(30分)Passage:In the small town of Willow Creek, there was once a charming old library that stood at the heart of the community. The library was a hub of learning and culture, where people of all ages would gather to read, discuss, and exchange ideas. The librarian, Mrs. Thompson, was known for her warm smile and vast knowledge of books. She had been working at the library for over 30 years and was deeply loved by everyone in the town.One day, the town’s mayor announced that the library was in danger of closing due to budget cuts. The community was shocked and immediately rallied to save their beloved library. They organized a series of events, including a book sale, a bake sale, and a benefit concert, to raise funds.The most successful event was the “Willow Creek Reads” program, where local authors were invited to read to the children and talk about their writing process. The children were excited and inspired, and the adults were reminded of the power of books to bring people together.As the days went by, more and more people began to donate books and moneyto the library. Mrs. Thompson was overwhelmed by the outpouring of support from the community. She knew that the library would not only survive but thrive.One evening, as Mrs. Thompson was organizing a new shelf of donated books, she noticed a mysterious note tucked inside one of the books. The note read, “To Mrs.Thompson, from the Friends of Willow Creek Library. We hope these books bring you joy and continue to inspire the community.”Mrs. Thompson smiled, knowing that the spirit of the library was alive and well.Blanks:1.The library in Willow Creek was a___________of learning and culture.2.Mrs. Thompson was___________for her warm smile and vast knowledge of books.3.The town’s mayor announced that the library was in___________due to budget cuts.4.The community___________to save their beloved library.5.The most successful event was the___________program.6.The children were___________and inspired by the local authors.7.The adults were___________of the power of books to bring people together.8.More and more people began to___________books and money to the library.9.Mrs. Thompson was___________by the outpouring of support from the community.10.The note was a___________from the Friends of Willow Creek Library.11.Mrs. Thompson smiled, knowing that the spirit of the librarywas___________and well.Questions:11.What was the note a___________from the Friends of Willow Creek Library?A)InvitationB)ComplaintC)Thank youD)ApologyAnswer:C) Thank you四、阅读理解(本部分有5大题,每大题9分,共45分)第一题Read the following passage and answer the questions that follow.The Internet has revolutionized the way we communicate, access information, and conduct business. With just a few clicks, we can connect with people from all over the world, access a vast amount of information, and even conduct transactions online. However, along with these benefits, the Internet has also brought about various challenges and risks. One of the most significant risks is the potential for cybercrime, which includes hacking, identity theft, and phishing.1.What is one of the major risks associated with the use of the Internet?A. Improved communicationB. Access to a vast amount of informationC. Potential for cybercrimeD. Increased business opportunities2.What are some examples of cybercrimes mentioned in the passage?A. Hacking, identity theft, and phishingB. Improved communication and access to informationC. Increased business opportunitiesD. Reduced need for physical interaction3.How does the Internet impact the way we conduct business?A. It reduces the need for physical interactionB. It increases the potential for cybercrimeC. It provides a platform for global communication and transactionsD. It eliminates the need for traditional banking and financial servicesAnswers:1.C2.A3.C第二题Passage:The rapid development of technology has greatly influenced the way people communicate. Social media platforms have become an integral part of daily life,allowing individuals to connect with others across the globe. However, this shift in communication has raised concerns about the impact on face-to-face interactions and the potential loss of traditional social skills.One of the most popular social media platforms is Instagram, which is known for its focus on visual content. Users can share photos, videos, and stories, and follow others who share similar interests. While Instagram can be a great way to stay connected with friends and discover new things, it also has its downsides.A recent study found that excessive use of Instagram can lead to feelings of loneliness and depression. The constant comparison with others’ seemingly perfect lives can create a sense of inadequacy. Additionally, the platform’s algorithm can create a filter bubble, where users are only exposed to content that aligns with their existing beliefs and interests, thus limiting their exposure to diverse perspectives.Despite these concerns, many people find Instagram to be a valuable tool for networking and personal growth. It can provide a platform for artists, writers, and entrepreneurs to showcase their work and connect with potential audiences. Moreover, it can be a source of inspiration and motivation, as users are exposed to the achievements and stories of others.Questions:1、What is the main topic of the passage?A) The benefits of using social media platforms.B) The negative effects of Instagram on social interactions.C) The history of social media platforms.D) The role of technology in modern communication.2、Which of the following is NOT mentioned as a potential negative effect of using Instagram?A) Feelings of inadequacy.B) Limited exposure to diverse perspectives.C) Improved communication skills.D) Increased feelings of loneliness and depression.3、What is the author’s attitude towards Instagram?A) Highly critical.B) Indifferent.C) Positive and supportive.D) Ambiguous.Answers:1、B) The negative effects of Instagram on social interactions.2、C) Improved communication skills.3、D) Ambiguous.第三题Reading Passage:In the small town of Greenfield, there was a long-standing tradition of the annual Greenfield Festival. The festival, which took place every autumn, broughttogether local artists, musicians, and performers from around the region. It was a time for celebration, a showcase of local talent, and a chance for the community to come together and enjoy the arts.One of the highlights of the festival was the “Greenfield Talent Show,” where local residents could audition to perform. This year, the talent show had a special twist: the winner would receive a scholarship to study music at a prestigious music school in the nearby city of Bluewater.Word Count: 102Questions:1、What is the main purpose of the Greenfield Festival?A) To promote tourism in GreenfieldB) To bring the community together and celebrate local artsC) To raise funds for charityD) To promote agricultural products2、Which event at the festival was of particular interest to this year’s participants?A) The art exhibitionB) The music concertC) The Greenfield Talent ShowD) The local craft fair3、What reward did the winner of the Greenfield Talent Show receive?A) A cash prizeB) A trip to the nearby cityC) A scholarship to study musicD) A trophyAnswers:1、B) To bring the community together and celebrate local arts2、C) The Greenfield Talent Show3、C) A scholarship to study music第四题Reading ComprehensionRead the following passage and answer the questions that follow.The rise of e-commerce has revolutionized the way people shop and has had a significant impact on traditional brick-and-mortar stores. Online shopping has become increasingly popular due to its convenience and the vast variety of products available. However, this shift has also brought about challenges and changes in the retail industry.One of the main advantages of e-commerce is the convenience it offers. Customers can shop from the comfort of their own homes at any time of the day or night. This eliminates the need to travel to physical stores and wait in long queues. Additionally, online platforms often provide detailed product descriptions, customer reviews, and even virtual try-ons, which can help customers make more informed purchasing decisions.Despite these benefits, e-commerce has also presented challenges fortraditional retailers. Many have had to adapt to the changing landscape by investing in their online presence and offering competitive pricing and customer service. However, some have struggled to keep up and have been forced to close their doors.The retail industry is also witnessing a shift in consumer behavior. Customers are becoming more environmentally conscious and are increasingly looking for sustainable and ethical products. This has led to a rise ineco-friendly shopping options and a decline in demand for fast fashion.1.What is the main advantage of e-commerce mentioned in the passage?A) Competitive pricingB) ConvenienceC) Eco-friendly optionsD) Detailed product reviews2.How has e-commerce affected traditional brick-and-mortar stores?A) They have become more profitable.B) They have had to adapt and invest in online presence.C) They have seen a significant increase in foot traffic.D) They have closed down due to increased competition.3.What is the trend in consumer behavior mentioned in the passage?A) Customers are looking for more affordable products.B) Customers are becoming more environmentally conscious.C) Customers are preferring fast fashion over sustainable options.D) Customers are no longer interested in online shopping.Answers:1.B) Convenience2.B) They have had to adapt and invest in online presence.3.B) Customers are becoming more environmentally conscious.第五题Read the following passage and answer the questions that follow.In recent years, there has been a growing interest in online education. This shift is primarily due to the convenience and flexibility it offers to students. Online courses allow individuals to learn at their own pace, from any location, and often at a lower cost compared to traditional in-person classes. However, despite these advantages, online learning also comes with its own set of challenges.One of the main concerns is the potential for reduced social interaction. In traditional classrooms, students have the opportunity to engage with their peers and professors, which can enhance their learning experience. Online students, on the other hand, may feel isolated and disconnected from the academic community. This can lead to a lack of motivation and engagement in the course material.Another challenge is the need for self-discipline. Online courses require students to be self-motivated and organized. Without the structure of a traditional classroom, students must set their own schedules and manage their time effectively. This can be difficult for some individuals, especially thosewho are accustomed to the routine of attending classes on campus.Despite these challenges, many online learners find that the benefits outweigh the drawbacks. They appreciate the ability to work around their other commitments, such as full-time jobs or family responsibilities. Additionally, online courses often provide access to a wider range of resources and expertise than traditional courses.1.The primary reason for the growing interest in online education is:a) the opportunity for social interactionb) the flexibility and convenience it offersc) the lower cost compared to traditional in-person classesd) the access to a wider range of resources2.What is one of the main concerns mentioned about online learning?a) The convenience of learning at one’s own paceb) The potential for reduced social interactionc) The lower cost of online coursesd) The increased access to expertise3.According to the passage, which of the following is a challenge for online learners?a) The ease of engaging with peers and professorsb) The need for self-discipline and organizationc) The lower cost of online coursesd) The ability to work around other commitmentsAnswers:1.b) the flexibility and convenience it offers2.b) The potential for reduced social interaction3.b) The need for self-discipline and organization五、补全对话(本大题有5小题,每小题3分,共15分)第一题A: Excuse me, could you help me with some English vocabulary?B: Sure, I’d be happy to. What would you like to know about?A: I need to expand my vocabulary for the college entrance exam. Can you suggest some useful words for an “Adult Higher Education” (AHLE) English test?B: Absolutely! Here are a few words and phrases that are often included in such exams:1.(______) - a higher level of education beyond high school.2.(______) - a system of post-secondary education that allows working adults to earn degrees.3.(______) - a person who is studying or has studied at a college or university.4.(______) - a course or program of study that leads to a degree or certification.5.(______) - a test taken by students to gain admission to a college or university.A: Great, thanks! What should I write in the blank spaces?B:1.(______) - A higher level of education beyond high school.2.(______) - A system of post-secondary education that allows working adults to earn degrees.3.(______) - A person who is studying or has studied at a college or university.4.(______) - A course or program of study that leads to a degree or certification.5.(______) - A test taken by students to gain admission to a college or university.答案:1.Degree2.Adult Higher Education (AHLE)3.College student4.Curriculum5.Admission test解析:1.Degree - This word is used to describe a higher level of education, which is a key concept in the context of college education.2.Adult Higher Education (AHLE) - This specific term refers to the system that caters to working adults who wish to pursue further education.3.College student - This phrase describes someone who is currently or has been enrolled in a college or university.4.Curriculum - This word refers to the courses or program of study that an educational institution offers.5.Admission test - This term refers to the test that students must take to be admitted to a college or university, which is a common requirement for higher education.第二题1.A: I’m sorry, but I can’t help you with that right now.B: Why not?A: Because I’m currently in a meeting.B: Oh, I see. Well, can I leave you a message?A: Certainly, you can.B: Thank you. I’ll just write down my number and call you back after the meeting.A: That sounds good.B: Is there anything specific you need help with?A: Yes, actually. I need some information about the new software package our company is considering.B: Of course. Let me check if I have that information available.A: Alright, take your time.B: I should be able to find it for you. Just a moment, please.A: No problem.B: There we go. I have the information you need.A: Great, thanks. Can you send it to my email?B: Absolutely. I’ll send it over right now.A: Perfect. I appreciate your help.B: You’re welcome. Feel free to call back if you need anything else.A: Will do. Have a good meeting.B: You too. Goodbye.1.A: I’m sorry, but I can’t help you with that right now.B: Why not?A: Because I’m currently in a meeting.B: Oh, I see. Well, can I leave you a message?A: Certainly, you can.B: Thank you. I’ll just write down my number and call you back after the meeting.A: That sounds good.B: Is there anything specific you need help with?A: Yes, actually. I need some information about the new software package our company is considering.B: Of course. Let me check if I have that information available.A: Alright, take your time.B: I should be able to find it for you. Just a moment, please.A: No problem.B: There we go. I have the information you need.A: Great, thanks. Can you send it to my email?B: Absolutely. I’ll send it over right now.A: Perfect. I appreciate your help.B: You’re welc ome. Feel free to call back if you need anything else.A: Will do. Have a good meeting.B: You too. Goodbye.答案:解析:The correct continuation of the dialogue is B because it maintains the context of the original message and provides a logical progression of the conversation. It addresses the initial reason for the inability to assist and then moves on to offering a solution (leaving a message) and asking for further details about the assistance needed. The dialogue then proceeds with the person finding the information, offering to send it via email, and concluding with a friendly farewell.第三题A: Excuse me, I’m looking for the English section of the Adult College Entrance Examination. Can you help me?B: Sure, follow me. You need to go to the second floor and then turn right. The English section is located in Room 202.A: Oh, okay. Thank you. By the way, what time does the exam start?B: The exam will begin at 9:00 a.m. sharp. Make sure you arrive 30 minutes early to get settled.A: Got it. I’ll be there on t ime. One more thing, is there a specific roomfor the English exam?B: Yes, it’s Room 202 as well. You’ll see a sign indicating the English section.A: Perfect. Thanks again for your help.B: You’re welcome. Good luck with your exam!Answer:B: Yes, it’s Room 202 as well. You’ll see a sign indicating the English section.Explanation:In this dialogue, the student is asking for directions to the English section of the exam. The answer to the question is found in the response by the staff member. They confirm that the English exam is held in Room 202, as indicated by a sign, providing clear information to the student.第四题A: Excuse me, I seem to have misplaced my calculator. Can you help me find it?B: Sure, where do you think you might have left it?A: I was working on this problem for our math class, and I think I might have left it on the desk.B: Okay, let’s check the desk first. Is this the one you’re looking for?A: No, that’s not it. It was smaller and black.B: Alright, let’s look over there by the window. Do you see anything that。
Psychology is a fascinating field that delves into the human mind and its processes. It is the scientific study of behavior and mental functions,encompassing a wide range of topics from the biological aspects of the brain to the social interactions of individuals. Here are some key areas and concepts that could be explored in an English essay about psychology:1.Historical Development:Discuss the evolution of psychology from its early philosophical roots to the establishment of it as a scientific discipline.Mention key figures like Sigmund Freud,Carl Jung,and B.F.Skinner,and their contributions to the field.2.Branches of Psychology:Psychology is a diverse field with various branches such as clinical psychology,cognitive psychology,developmental psychology,social psychology, and more.Each branch focuses on a different aspect of human behavior and mental processes.3.Theories and Models:Explore the different theories that have shaped the understanding of the human mind,such as behaviorism,cognitive theories, psychoanalytic theories,and humanistic psychology.Discuss how these theories have been applied in practice.4.Research Methods:Psychology relies heavily on empirical research.Discuss the various research methods used in psychology,including experiments,surveys,case studies,and longitudinal studies.Highlight the importance of ethical considerations in conducting research.5.Cognitive Processes:Delve into how humans perceive,learn,remember,and think. Discuss topics such as attention,memory,problemsolving,and decisionmaking.6.Emotional and Behavioral Disorders:Address the classification and treatment of various mental health disorders,such as anxiety disorders,mood disorders,and personality disorders.Discuss the role of psychologists in diagnosing and treating these conditions.7.Social Psychology:Examine how individuals are influenced by others and their social environment.Discuss topics like conformity,obedience,social influence,and group dynamics.8.Developmental Psychology:Explore how individuals develop from infancy to old age. Discuss stages of development,cognitive development,and the impact of social andcultural factors on development.9.Applied Psychology:Discuss how psychology is applied in various settings,such as education,business,sports,and healthcare.Highlight the role of psychologists in improving performance,wellbeing,and mental health.10.Ethical Issues:Address the ethical dilemmas that psychologists may face,such as confidentiality,informed consent,and the use of animals in research.11.Future of Psychology:Speculate on the future trends and developments in the field of psychology,including advances in technology,new research methodologies,and the potential for interdisciplinary integration.12.Cultural Perspectives:Discuss how cultural differences can influence psychological theories and practices.Consider the importance of cultural competence in understanding and treating diverse populations.13.Neuropsychology:Explore the relationship between the brain and behavior,focusing on how brain injuries or diseases can affect cognitive and emotional functioning.14.Positive Psychology:Discuss the relatively new field of positive psychology,which focuses on the study of happiness,wellbeing,and human strengths.15.Psychological Assessment:Explain the various tools and techniques used by psychologists to assess cognitive abilities,personality traits,and mental health status.When writing an essay on psychology,it is crucial to use clear and concise language, provide examples to support your arguments,and cite reputable sources to back up your claims.Additionally,it is important to maintain an objective and scientific tone throughout the essay.。
江苏省南京市六校联合体2024-2025学年高二上学期10月月考英语试题一、听力选择题1.What seems to be the woman’s problem?A.She failed to contact the bank manager.B.She got her bank card stuck in the A TM.C.She can’t operate the machine.2.When will the play show?A.On the 15th.B.On the 16th.C.On the 17th.3.What will the woman do next?A.Park her car.B.Look at the stars.C.Fetch the telescope. 4.Why is the boy unhappy?A.He feels lonely.B.He missed his flight.C.He’s worried about his parents.5.What are the speakers mainly talking about?A.Their favorite scientists.B.The old math books.C.The new science books.听下面一段较长对话,回答以下小题。
6.What is the relationship between the speakers?A.Brother and sister.B.Husband and wife.C.Co-workers.7.What does the woman offer to do?A.Give the man two tickets.B.Book tickets for the man.C.Watch a movie with the man.听下面一段较长对话,回答以下小题。
Bridge SubstructurePiers and Abutments1 Piers1.1 pier typesPiers are intermediate supports in a multi-span bridge system. All feasible pier types must be considered in the preliminary phases of the project.1.1.1 Cap-and-column Type PiersCap-and-column type piers have two or more circular or rectangular colunms connected on top with a cap (a reinforced concrete beam that supports the superstrucure ) .Generally,the pier cap ends will be cantilevered.For columns greater than 100 to 150 FT,the use of a compression strut at mid-height,similar to the pier cap,shall be investigated.The individual columns will be supported on an appropriate foundation.1.1.2 T-Type or Hammerhead or Wall Type PiersT-type or Hammerhead piers have a deep rectangular tapered beam carrying the superstructure supported on a single wide rectangular or oval column in the middle.For wall type piers,the width of the rectangular colunm will be very close to the length of the pier cap.The single column will be supported on an appropriate foundation.In some situations,the feasibility of using a single large circular column instead of a wide rectangular or oval column has to be investigated during the preliminary design phase of the project.1.1.3 Post-Tensioned Concrete/Integral Pier CapsTo satisfy the vertical clearance requirement beneath a pier cap,a post-tensioned or integral pier cap shall be investigated.1.1.4 Steel Pier CapsSteel pier caps are fracture critical.If used,the design shall allow for reasonable access to the interior for future maintenance,inspection and repair.1.2 Piers Design CriteriaClass B Concrete with a compressive strength of 3000 PSI should be used for most piers.Class B Modified concrete with a compressive strength of 4000 PSI may be used,if required of strength.For the strength and extreme event limit states,the Designer is strongly encouraged to use the strut and tie model for thick concrete elements(e.g.footings,pile caps and pier caps).Use this method to determine internal force effects near supports and points of concentrated loads.Moment redistribution shall be used where appropriate.1.2.1 Pier CapsAll pier caps must be wide enough to accommodate the bridge bearings and jacking points.The edge of the bearingmasonry plates must be a minimum of three inches from the face of the pier cap.Instances of pier caps being wider than the column,necessitated by skewed bearings and dual bearings such as theose found on prestressed concrete beam superstructures are acceptable.Pier cap depths shall be determined by strength and clearance requirements.The minimum size is 3 FT vertically by 2.5 FT horizontally and must extend 1 FT beyond the face must be haunched.A 2:1 haunch ratio is prefferred.The ends of the pier caps may be either plane verticallyor shaped(i.e.cylindrical to mirror the columns).1.2.2 Pier ColumnsThe minimum longitudinal column diameter or stem thickNess shall be 3 FT. Column tapers or section changes shall not be used unless a detailed study proves that they are cost-efficient.Generally,these forming costs are very high.Consider hollow shafts for piers in excess of 100 FT.Multi-column piers should generally not be used in a flood plain.Single circular column,T-type or wall type piers may be used in the flood plain.Single circular column,T-type or wall type piers may be used in the flood plain with rounded ends and shall be oriented parallel to the stream flow.2 Abutments2.1 Abutment TypesAbutments are structures positioned at the beginning and end of a bridge,which support the superstructure and approach roadway and retains the earth embankment.Abutments can be classified into the following five types:2.1.1 Wall AbutmentThis type of abument,also known as a full height abutment,may be used when right-of-way is critical or the site does not permit a longer bridge with sloping embankments.Span lengths can be reduced using a wall type abutment.The footing may transfer loads by direct bearing(spread footing) or it may be supported on piles or drilled caissons.The maximum exposed face should generally be 30 FT,measured from gutter line to ground line in the profile view.Taller heights may be permitted ,with permission of the Bridge Project Manager,when the negative effects of a tall structure on the traveling public or aesthetics are not a governing factor.Otherwise,where walls greater than 30 FT are required,a stepped(terraced) wall configuration shall be used.2.1.2 PedestalsThe beam seat is supported on columns/drilled caissons or pedestals resting on individual footings.This configuration is usefull for meeting unique construction problems,e.g. widely varying elevations of competent rock.2.1.3 Stub AbutmentStub abutments are relatively short abutments that resemble wall type abutments.These abutments are generally placed on the approach embankment and are supported on rock,piles or drilled caissons.2.1.4 Integral AbutmentIntegral abutments are generally short abutments supported on a single row of piling.These abutments,like stub abutments,are generally placed on approach embankments and are well suited for bridges with limited thermal movements.The ends of the bridge beams are cast directly into the abutments,thereby eliminating the need for expansion devices.2.1.5 Semi-Integral AbutmentSemi-integral abutments can be either wall or stub type abutments.The difference between a semi-integral and an integral abutment is that for semi-integral abutments,the beams are cast in a closure diaphragm that is structurally independent from the stem.This type also eliminates the need for expansion devices.See Section 3.9 for limitations on the use of semi-integral abutments.2.1.6 WingwallsWingwalls are walls on either side of an abutment used to retain the roadwayembankment.Wingwalls can be constructed of cast-in-place concrete or MSE walls and shall be designed as retaining walls.They shall be sufficiently sized to prevent the roadway embankment from spilling onto the abutment seats or into clear area under the bridge.U-shaped or turned-back wingwalls are commonly used in embandment situations and straight wings are used in cut sections.Flared wingwalls between these extremes can also be appropriate based on site conditions.The Designer must study the existing and proposed surfaces to determine which type of wingwall best fits the site.Wingwalls with a tapered bottom surface shall be avoided due to compaction difficulties beneath the wall.The top surface of U-shaped wingwalls may be tapered parallel to the roadway slope to match the finished grade.2.2 Abutment Design CriteriaThe main parts of an abutment are the bridge seat,backwall,stem,wingwalls,and foundation.Several types of abutments can be utilized for a particular bridge site.Aesthetics can sometimes be a factor when selecting an abutment type.Class B Concrete with a compressive strength of 3000 PSI should be used in most abutments.The minimum reinforcing throughout the abutment and wingwalls shall be NO.5 bars spaced at 1 FT. All reinforcing steel above the beam seat shall be epoxy coated.2.2.1 Bridge SeatThe width of the bridge seat must be sufficient to accommodate the beams or girders,jacking operations and meet the seismic requirements of the Governing Specifications.Adequate room between the beams or girders and the backwall shall be provided to allow for expansion joint inspection,where applicable.Due to roadway cross-section slopes or skewed abutments,it may be necessary to provide beam seats of different elevations.When detailing abutments,the difference in elevations between adjacent beam seats may be achieved by stepping the top of the stem,or by utilizing a sloped stem to eliminate the effects of cracking in large bridge seat steps.The sloped stem option is preferred when the slope of the beam allows.2.2.2 BackwallsA backwall shall be provided on all bridges to retain the embankment behind the bridge,support the approach slab(if applicable) and to protect the bridge seat from water intrusion.However,with the approval of the Director of Engineering Division,some prestressed box beam bridges may not require the use of a backwall.The minimum thickNess for a backwall shall be 1 FT. For backwall requirements on jointless bridges see Section 3.9.2.2.3 StemThe stem is a structure that retains the embankment behind the abutment and transmits the loads from the superstructure to the foundation.While there is no minimum thickNess requirement,the stem thickNess shall be designed to support the required loading and provide sufficient space for bearing devices . Stems may be level,stepped or sloped based on bridge geometry(see Section 3.8.2).2.2.4 WingwallsWingwalls must be long enough to retain the roadway embankment based on the embankment slopes.The positioning of the wingwalls depends on the site itself(e.g.,cut vs.fill,etc.).The Designer must study the existing and proposed contours and determine which type of wingwall best fits the site . Approach roadway slopes must be considered.。
Integrity is a fundamental value in society,guiding individuals to act with honesty and responsibility.Heres an essay that delves into the importance of integrity and its impact on personal and professional life.Title:The Essence of IntegrityIntroduction:Integrity is the cornerstone of trust and respect in any relationship.It is the quality of being honest and having strong moral principles.This essay will explore the significance of integrity in various aspects of life,from personal development to professional success. Body Paragraph1:Personal IntegrityPersonal integrity is the adherence to ones own moral code and values.It is about being true to oneself and maintaining honesty in all interactions.Examples of personal integrity include keeping promises,being reliable,and standing up for what one believes in,even when it is challenging.Body Paragraph2:Professional IntegrityIn the workplace,integrity is crucial for building a reputation of trustworthiness and reliability.Employers value employees who are honest and ethical in their dealings. Professional integrity involves being accountable for ones actions,avoiding conflicts of interest,and maintaining confidentiality when necessary.Body Paragraph3:The Consequences of Lacking IntegrityThe absence of integrity can lead to a loss of trust,damaged relationships,and even legal consequences.Dishonesty can erode the foundation of any relationship,whether personal or professional.Examples of the consequences of dishonesty include loss of employment,damaged reputation,and strained personal relationships.Body Paragraph4:Cultivating IntegrityDeveloping integrity is a lifelong process that requires selfreflection and a commitment to ethical behavior.It involves recognizing ones values and acting in accordance with them.Some ways to cultivate integrity include setting personal standards,seeking role models who exhibit integrity,and engaging in open and honest communication.Body Paragraph5:The Impact of Integrity on SocietyA society that values and practices integrity is more likely to experience social harmony and stability.Trust in institutions and among individuals fosters cooperation andcollaboration.Integrity in leadership is particularly important,as leaders set the tone for societal values and behaviors.Conclusion:Integrity is not just a personal virtue but a societal necessity.It is the bedrock upon which trust,respect,and cooperation are built.By embracing integrity in our daily lives,we can contribute to a more honest,transparent,and ethical world.Reflection Questions:1.How has integrity impacted your life or the lives of those around you?2.Can you recall a time when you had to make a choice between integrity and personal gain?What did you choose,and why?3.What are some practical steps you can take to ensure you maintain integrity in your daily life?This essay aims to highlight the importance of integrity and encourage readers to reflect on their own actions and decisions,fostering a deeper understanding of the value of being honest and ethical in all aspects of life.。
《信息检索》课程报告项目名称:水工建筑物中大体积混凝土裂缝的防治学号:1160220039姓名:张鑫专业:水利工程学院:水利水电学院四、文献检索范围及检索策略(一)文献检索范围国内数据库:1.超星数字图书馆1992—2012.2KI中国期刊全文数据库2000—2012.53.万方数据知识服务平台1989—2012.54.校内学位论文全文数据库1989—2012.5KI中国优秀博硕士学位论文全文数据库1989—2012.56.维普中文科技期刊库(引文)1989—2012.57.维普中文科技期刊库(全文)1989—2012.58.全国报刊索引数据库1989—2012.59.国家科技成果网1978-2012.510.高校专利信息服务平台2000-2012.511.互联网相关中文网站国外数据库:1.Engineering Village2(EI)1969-2012.52.Conference Proceedings Citation Index(原ISTP)1969-2012.53.CALIS数据库-西文期刊目次数据库(CCC)1992-2012.54.PQDT(Abstract)全球博硕士论文-科学与工程卷1980-2012.55.SpringerLink1990-2012.56.ISI Web of Science(SCI)1950-2012.57.ScienceDirect(SD)1990-2012.58.IEEE/IET Electronic Library(IEL)1990-2012.59.IWA数据库(国际水协会)(二)检索策略检索词:1大体积混凝土(mass concrete)2水工建筑物(hydraulic structure)3裂缝(carck)4温度裂缝(Temperature cracks)5应力裂缝(stress crack)检索式:A.1and2and(3or4)B.1and2and(3or4)and5五、检索结果运用以上检索策略在以上国内、外数据库中检索到与该委托项目相关的文献共计30余篇。
Field Behavior of an Integral Abutment BridgeSupported on Drilled ShaftsPhillip S.K.Ooi,P .E.,M.ASCE 1;Xiaobin Lin 2;and Harold S.Hamada,P .E.,F.ASCE 3Abstract:The abutments of integral bridges are traditionally supported on a single row of steel-H-piles that are flexible and that are able to accommodate lateral deflections well.In Hawaii,steel-H-piles have to be imported,corrosion tends to be severe in the middle of the Pacific Ocean,and the low buckling capacity of steel-H-piles in scour-susceptible soils has led to a preference for the use of drilled shaft foundations.A drilled shaft-supported integral abutment bridge was monitored from foundation installation to in-service behavior.Strain gauge data indicate that drilled shaft foundations worked well for this integral bridge.After 45months,the drilled shafts appear to remain uncracked.However,inclinometer readings provide a conflicting viewpoint.Full passive earth pressures never developed behind the abutments as a result of temperature loading because thermal movements were small and the long term movements were dominated by concrete creep and shrinkage of the superstructure that pulled the abutments towards the stream.In the stream,hydrodynamic loading during the wet season had a greater effect on the abutment movements than seasonal temperature cycling.After becoming integral,the upright members of the longitudinal bridge frame were not vertical because the excavation and backfilling process caused deep seated movements of the underlying clay resulting in the drilled shafts bellying out towards the stream.This indicates the importance and need for staged construction analysis in design of integral bridges in highly plastic clays.Also,the drilled shaft axial loads from strain gauges are larger than expected.DOI:10.1061/͑ASCE ͒BE.1943-5592.0000036CE Database subject headings:Bridge abutments;Drilled shafts;Strain gages;Earth pressure;Moment;Axial loads .Author keywords:Integral abutment bridge;Drilled shaft;Strain gage;Inclinometer;Earth pressure;Moment;Axial load .IntroductionIntegral abutment bridges ͑IABs ͒are jointless bridges that enjoy the following advantages over conventional bridges ͑Arockiasamy et al.2004;Hassiotis and Roman 2005;Kunin and Alampalli 2000;Mistry 2005;Wasserman and Walker 1996͒:1.Lower maintenance costs due to elimination of joints andbearings.2.Simpler and more economical construction ͑e.g.,only asingle row of vertical piles is needed at the abutment plus expansion joints and bearings are eliminated ͒.3.Added redundancy and capacity during seismic events andagainst buoyancy loads during flooding and wave loading during hurricanes or tsunamis.4.Improved ride quality.5.Integral abutments and piles help resist uplift forces actingon the beams at the end spans.In conventional bridges where the beam is not structurally connected to the abutment,uplift of beams at the end spans can occur during deck placement and during vehicular movement.6.Integral abutments spread the lateral loads throughout thestructure/soil system so that all supports accommodate these loads.This reserve capacity is not available in conventional bridges since the lateral loads are not distributed to the abut-ments.7.Bridge replacements can be accomplished easily with IABssince they do not require large footings and they can be readily constructed behind existing buried foundations with-out the need for large excavations.Despite the significant advantages,there are problems associ-ated with IABs,most of which arise from elimination of joints thereby forcing lateral movements to occur at the abutments.In both conventional bridges and IABs,lateral movements are caused by earth pressures,hydrostatic,traffic,impact,wind,and seismic loading.However,integral abutments are subject to the following additional superstructure-induced lateral loads not ex-istent in conventional bridges:͑a ͒thermal expansion and contrac-tion;͑b ͒concrete shrinkage ͑change in volume under zero stress ͒;and ͑c ͒concrete creep ͑change in volume under constant stress ͒.Excessive lateral movements may result in the following problems:1.Piles that support integral abutments are subject to bending,which can lead to formation of plastic hinges.To better ac-commodate lateral deflections,it is desirable to increase pile flexibility by supporting integral abutments on a single row of vertical steel-H-piles.1Associate Professor,Dept.of Civil and Environmental Engineering,Univ.of Hawaii,Holmes Hall 383,2540Dole Street,Honolulu,HI 96822͑corresponding author ͒.E-mail:ooi@ 2Former Research Assistant,Dept.of Civil and Environmental Engineering,Univ.of Hawaii,2540Dole Street,Honolulu,HI 96822.E-mail:xiaobin@ 3Emeritus Professor,Dept.of Civil and Environmental Engineering,Univ.of Hawaii,Holmes Hall 383,2540Dole Street,Honolulu,HI 96822.E-mail:hamada@Note.This manuscript was submitted on June 5,2008;approved on February 16,2009;published online on April 14,2009.Discussion period open until June 1,2010;separate discussions must be submitted for indi-vidual papers.This paper is part of the Journal of Bridge Engineering ,V ol.15,No.1,January 1,2010.©ASCE,ISSN 1084-0702/2010/1-4–18/$25.00.4/JOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .Table 1.List of Field Instrumented IABs in the United StatesReferences Bridge name State Length ͑m ͒Skew angle ͑degrees ͒Numberof spans Abutment foundations InstrumentationGoel ͑1997͒US101/Painter St.Overpass California 8138.9214and 16concrete friction piles20strong motion sensorsin the structure and the free-fieldFrosch et al.͑2005͒SR18BridgeIndiana1128514in.concrete filled tube pilesStrain gauges-piles,tiltmeters-abutment,convergence meters-abutment displacement Girton et al.͑1991͒Boone River BridgeIowa 99454HP 10ϫ42piles driven in predrilled holes filled with loose sand Linear variable differential transformers ͑LVDTs ͒-longitudinal expansion of the deck,thermocouples-air and deck temperature,strain gauges-pilesGirton et al.͑1991͒Maple River Bridge Iowa 98303HP 10ϫ42piles driven in predrilled holes filled with loose sand LVDTs-longitudinal expansion of the deck,thermocouples-air and deck temperature,strain gauges-pilesAbendroth andGreimann ͑2005͒Guthrie County Bridge Iowa 9730310HP 10ϫ42piles oriented for strong-axis bendingDisplacement transducers-abutment,tiltmeters-pile cap,strain gauges-piles and girders,thermocouples-air and superstructure temperatureAbendroth andGreimann ͑2005͒Story County BridgeIowa 611537HP 10ϫ42piles oriented for strong-axis bending.Displacement transducers-abutment,tiltmeters-pile cap,strain gauges-piles and girders,thermocouples-air and superstructure temperatureAbendroth et al.͑2007͒Tama County Bridge Iowa 34201712in.ϫ12in.prestressed concrete piles.Displacement transducers-abutment,strain gauges-piles,thermocouples-superstructuretemperatureHartt et al.͑2006͒Nash Stream BridgeMaine 303514HP 14ϫ89piles oriented for strong-axis bending and driven to bedrock Strain gauges-piles,inclinometer-piles,extensometers-top of each pile,thermistors-concrete deck,steel girders and air temperature,vibrating wire piezometer-pore pressure,earthpressure cells-abutmentSandford and Elgaaly ͑1993͒Forks Bridge Maine 50201Shallow foundations Earth pressure cells-abutment,resistancetemperature indicators-air temperature DeJong et al.͑2004͒Miller River BridgeMassachusetts 82038HP 10ϫ57pilesEarth pressure cells-abutment,joint meters-longitudinal and transverse displacements of superstructure,tiltmeters-abutment,temperature gauges-under bridge deck,strain gauges-piles Bonczar et al.͑2005͒Orange-Wendell BridgeMassachusetts 82038HP 10ϫ57pilesInclinometers-piles,tiltmeters-abutment,joint meter-abutment,strain gauges-piles and girders,earth pressure cells-abutmentLawver et al.͑2000͒—Minnesota 66036HP 12ϫ53piles oriented for weak-axis bending.Horizontal extensometers-abutment,tiltmeters-abutment,strain gauges-piles,approach slab,prestressed girders and concrete deck,earth pressure cells-abutmentKamel et al.͑1996͒—Nebraska 500215HP 10ϫ42piles and 112ϫ12in.prestressed concrete pile located between the steel-H-pilesInclinometer-piles,extensometer tape-bridge deck length changes,mercury-in-glass thermometer-temperature for tape length correctionHassiotis et al.͑2005͒Scotch Road over I-95BridgeNew Jersey 9115219HP 14ϫ102piles oriented for weak-axis bendingStrain gauges-piles,tiltmeters-rotation of connection between abutment and stringers,displacement transducers-longitudinaldisplacement of the abutment,temperature sensors-top of abutment,thermocouples-deck,earth pressure cells-abutment Jayakumaran et al.͑2005͒Belt Parkway BridgeNew York 660316in.diameter tapertube piles No informationJorgenson ͑1983͒Cass County BridgeNorth Dakota 13706HP 10ϫ42pilesoriented for weak-axis bendingInclinometers-piles and abutment,strain gauges-piles,thermocouples-air and deck temperatureJOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010/5D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .2.The axial pile capacities may be reduced,which can limit the length of IABs ͑Greimann and Wolde-Tinsae 1998͒.3.Back and forth movements can result in settlement of theapproach fill,which can in turn result in the formation of a void behind the abutment.Water entering may then lead to erosion and possible undermining of the abutment.4.Wing walls can rotate and crack due to contraction of thesuperstructure ͑Wolde-Tinsae and Klinger 1987͒.5.If the bridge is skewed,the lines of action of the lateral soilloads on opposite abutments will not coincide.These lateral loads will cause unbalanced moments in a horizontal plane ͑Burke 1996͒.To better understand their behavior,several IABs throughout the country have been instrumented and monitored,a summary of which is shown in Table 1.With a few exceptions,the majority of the instrumented IABs are supported on steel-H-piles to provide flexibility necessary to minimize the attraction of large lateral loads to the foundation and abutment.In Hawaii,steel-H-piles have to be imported,corrosion tends to be severe in the middle of the Pacific Ocean and the low buckling capacity of steel-H-piles in scour-susceptible soils has led to a preference for the use of large diameter concrete deep foundations.A drilled shaft-supported IAB was instrumented to study its behavior during and after construction.Data collected over a 45-month-period pro-vided information regarding lateral movements and other behav-ioral aspects that are useful for future design of IABs supported on concrete deep foundations.Project DescriptionThe Kii Bridge spans over the Ohia Stream in the town of Kahuku on the northern portion of the island of Oahu,Hawaii ͑Fig.1͒.This nonskewed,single-span bridge is 17-m-wide and 24.4-m-long and has two travel lanes running in a northwest ͑NW ͒-southeast ͑SE ͒direction ͓Fig.2͑a ͔͒.6.1-m-long approach slabs are rigidly connected to each abutment.Wing walls are ori-ented parallel to the longitudinal bridge axis.Each abutment wall is supported on a single row of five 3.66-m-spaced,23.2-m-long drilled shafts,which step-tapers in diameter from 1.22m ͑El.0.3to El.Ϫ4.1m mean sea level or MSL ͒,to 1.07m ͑El.Ϫ4.1to El.Ϫ9.3m ͒,to 0.914m ͑El.Ϫ9.3to El.Ϫ22.9m ͒.Hydraulic design constraints required a thin superstructure so as to maximize the opening below for unobstructed stream dis-charge.A total of twelve 610-mm-thick,steam-cured,precast con-crete voided planks overlain by a 127-mm-thick concrete topping were used as decking.The precast planks were prestressed andpost-tensioned.To reduce shrinkage and creep,the concrete in the precast planks and deck topping was dosed with a shrinkage-reducing admixture.Construction SequenceThe construction sequence and timeline are summarized in Table 2.The abutments were built in two pours ͑stem followed by the corbel above ͒.Backfilling behind both abutments allowed crane access for lifting and placing the precast planks.Table 1.͑Continued.͒References Bridge nameState Length ͑m ͒Skew angle ͑degrees ͒Numberof spans Abutment foundations InstrumentationFennema et al.͑2005͒—Pennsylvania5238HP 12ϫ74piles oriented for weak-axis bending Strain gauges-piles and girders,earth pressure cells-abutment,extensometers-abutment displacements,tiltmeters-abutment rotation and girder rotationHoppe and Gomez ͑1996͒Rte 257over I-81Virginia 9852Steel pilesEarth pressure cells-semi-integral abutmentHoppe ͑2005͒Jackson River BridgeVirginia 10103HP 10ϫ42piles driven to bedrockEarth pressure cells-abutment,strain gauges-girders,displacement transducers-abutment,tiltmeters-abutmentFig.1.Project location6/JOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .Subsurface ConditionsThe subsurface soils ͓Fig.2͑b ͔͒consist of a 1.4-m-thick fill un-derlain by 18.4-to 20-m-thick alluvium underlain by an older alluvium ͑Geolabs,Inc.2003͒.The alluvium consists of a high plasticity silty clay ͑CH–plasticity index=53%,liquid limit =85%͒based on the Unified Soil Classification System.Standard penetration test blow counts in the alluvium ranged from 8to 36.Natural water contents in the alluvium ranged from 21%near the ground surface to 76%at depth,indicating that the alluvium be-comes less preconsolidated with depth.The older alluvium was described as extremely weathered basaltic gravel,cobbles,and boulders.The backfill behind the abutment wall consists of a well-graded gravel ͑GW ͒underlain by controlled low strength material ͑CLSM or flowable fill ͒.CLSM was used to direct subsurfacewater into the weep holes.The CLSM mix had a slump of 200mm Ϯ50mm,a design strength ranging from 345to 1030kPa and a unit weight of 20.4kN /m 3.Instrumentation ResultsThe bridge was monitored using 74vibrating wire instruments to capture critical parameters along its centerline ͓Fig.2͑b ͔͒.A total of 40strain gauges were placed in the concrete topping,precast planks,abutment wall,and drilled shafts,28inclinometers were placed in the abutment wall and drilled shafts and 6contact pres-sure cells were placed behind the abutment walls.The inclinom-eter tubes were placed along the centroidal axis of the abutment and drilled shafts with the grooves oriented parallel to the longi-tudinal bridge axis.Strain gauges were placed in pairsdiametri-Cell Cluster of strain gages in Fig.2.Kii Bridge ͑a ͒plan;͑b ͒elevation with instrumentation layout and subsurface profileJOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010/7D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .cally opposite each other along the longitudinal bridge axis.Sixteen strain gauges were installed in the precast planks and topping to monitor shrinkage and creep in the concrete deck.Initially,gauge and temperature readings were collected manu-ally using a readout unit.After December 23,2004,data was collected remotely through two dataloggers connected to all the instruments except the 16strain gauges in the superstructure,which were read manually.All the gauge readings were corrected for temperature.From December 23,2004to March 13,2006,data was acquired every 2h.Thereafter,data was acquired every 6h.Field Observation Abutment MovementVariation of movement versus time for the NW abutment is shown in Fig.3͑a ͒.Positive values represent movement towards the stream.Since the displacements in both abutments are gener-ally similar,only the top inclinometer from the NW abutment is shown for brevity.The top inclinometer is 1.56m below the top of the bridge.Initial readings were measured on June 1,2004,after constructing the abutment stem and prior to any backfilling.The effects of plank placement and pouring of the topping are notated in Fig.3͑a ͒.The displacement profile is plotted versus depth for selected events in Fig.4.Superimposed on Fig.3͑a ͒is the Kahuku air temperature downloaded from the Western Regional Climate Center ͑Western Regional Climate Center 2008͒website.After the bridge deck became integral with the abutments,the minimum and maximum recorded air temperatures were 14.4°C ͑58°F ͒and 29.4°C ͑85°F ͒,respectively.The following observations are offered in chronological order:1.June 16,2004through September 10,2004—after backfillingwith CLSM and well-graded gravel behind the abutment,the drilled shaft bellies out by about 3–4mm towards the stream indicating deep seated movement of the highly plastic allu-vium ͑Fig.4͒.These movements occurred before the super-structure is in place.In design,it is customary to assume that the drilled shaft and abutment form the “vertical”part of a frame for longitudinal analysis of the IAB.These movementsindicate that this is not the case suggesting that a staged construction analysis to obtain a predeflected profile of the frame may be important when the subsurface soils consist of soft highly plastic clays.2.September 8through 29,2004—precast planks were placed on the outer 150mm of the top of the 1.37-m-wide corbel on September 8and 9,2004.This resulted in the shaft and abut-ment bellying out even more ͑5mm ͒towards the stream ͑Fig.4͒.Despite the eccentric loading,there was little rota-tion of the abutment and shaft observed.This can be ex-plained as follows:to hoist the precast planks,one crane behind each abutment was utilized.The crane surcharge in-creased the lateral stress on the wall thereby counteracting any tendency for the wall to rotate.Pouring of the topping and diaphragm on September 29,2004caused minimal change in the deflected profile ͑October 1,2004reading in Fig.4͒.This date represents the integration of the abutment and superstructure.3.September 29through mid-January,2005—after the abut-ment became integral with the superstructure,the shaft and abutment movement reversed towards the backfill ͓Fig.3͑a ͔͒.This movement continued through mid-January 2005.This direction of movement is not due to temperature loading be-cause the direction of movement is more consistent with “ex-pansion”of the superstructure,which is not expected during the winter months.During this period,the earth pressure in-creased ͑Fig.3͑b ͒͒substantiating the backward movement.The rationale for this movement is explained in Item 7below.4.April 27,2005—the deflected profile of the NW abutment at two extreme air temperatures within the same day is shown in Fig.5.With a temperature swing of 8.9°C ͑16°F ͒,the thermal-induced movement,⌬T ,was estimated to be 1.1mm as follows:⌬T =␣⌬TL 2͑1͒where ␣=coefficient of thermal expansion for concrete ͑10−5/°C ͒;⌬T =air temperature change;and L =bridge span length.The closeness of the calculated and measured values may be fortuitous considering that strictly ⌬T should be theTable 2.Construction TimelineEventDateNW abutment SE abutment Install instrumented drilled shaftsApril 21,2004April 30,2004Construct abutment wall to El.2.51m June 1,2004June 24,2004Backfill with CLSM to El.1.75m June 16,2004June 25,2004Construct cap beamJune 22,2004July 2,2004Complete backfilling behind abutment with GW July 2,2004July 15,2004Prestress instrumented precast planks July 6and August 4,2004Post-tension instrumented precast planks August 23and 25,2004Place precast planks on abutmentsSeptember 8and 9,2004Pour topping/diaphragm to make bridge integral September 29,2004Pour approach slabOctober 26,2004Pour jersey barriers and place precast railings Between October 15and November 4,2004Load test with truck containing 6yd.3concrete November 4,2004Install data acquisition system December 23,2004December 22,2004Open Kii Bridge to trafficJanuary 3,20058/JOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .-4-3-2-10123456/1/049/29/041/27/055/27/059/24/051/22/065/22/069/19/061/17/075/17/079/14/071/12/08DateD i s p l a c e m e n t (m m )05101520253035A i r T e m p e r a t u r e (oC )-101020304050606/1/049/29/041/27/055/27/059/24/051/22/065/22/069/19/061/17/075/17/079/14/071/12/08Date L a t e r a lE a r t h P r e s s u r e (k P a )(b)(a)-1200-1000-800-600-400-200DateS t r a i n (m m /m m X 10-6)(c)Fig.3.͑a ͒Movement at the NW abutment versus time;͑b ͒lateral earth pressure in the GW fill ͑El.2.69m ͒and CLSM ͑El.0.86m ͒at the NW abutment versus time;and ͑c ͒longitudinal strains in precast plank at the NW abutment versus timeJOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010/9D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .effective bridge temperature,which is related to the shade temperature,solar-radiation,wind speed,material properties,surface characteristics,and section geometry ͑Oesterle and V olz 2005͒.5.May 16through 20,2005—when the movements are replot-ted using an expanded time-axis ͑Fig.6͒,it can be seen that thermal-induced movements are consistent with the daily temperature swings.When the temperature escalates from morning to afternoon,the abutments move towards the back-fill and the reverse occurs from afternoon to night.These daily temperature swings are more pronounced in the south-facing NW abutment than in the SE abutment,which faces north.This was also observed in other integral bridges ͑e.g.,Bonczar et al.2005͒.6.Winter 2005through winter 2008—in the long term,the abutment tends to move towards the stream ͓trendline in Fig.3͑a ͔͒although the magnitude of movement is small ͑Ͻ2mm ͒over a 45-month-period.This is due to ͑a ͒creep and shrinkage of the concrete in the superstructure and also possibly due to ͑b ͒continuous raveling of soil into a gap created behind the abutment during cycling.The long term movement trend correlates well with the increase in com-pressive strain in the superstructure ͓Fig.3͑c ͔͒and the de-crease in earth pressure ͓Fig.3͑b ͔͒over time.Thus for short-span IABs in the tropics,movement due to concrete creep and shrinkage may dominate relative to temperature oscilla-tions such that excursions of earth pressure into the passive state during thermal loading may not even materialize.7.Winter 2005through winter 2008—seasonally,the abutment tends to move towards the backfill ͓displacements tend to become negative in Fig.3͑a ͔͒in the winter and towards the stream in the summer.The peak-to-peak movement ampli-tude is on the order of 1–2mm.Ordinarily however,the superstructure expands in the summer and contracts in the winter so this trend is contrary to what is expected.Based on measurements made in the Ohia stream during site visits and based on historical flow measurements in other nearby streams ͑there are no USGS gauges in Ohia Stream—U.S.Geological Survey 2008͒,the historical stream levels are consistently higher in the winter and lower in the summer ͓Fig.7͑a ͔͒.This is reasonable because the winter months correspond to the wet season in Hawaii ͓Fig.7͑b ͔͒.A higher stream level will push the abutment towards the backfill.Therefore,the seasonal abutment wall movements appear to be governed more by changes in the stream levels rather than temperature loading.This may be the case for short-span IABs in the tropics with relatively low seasonal temperature fluctuations.In all the displacement profiles ͑Fig.4͒,the drilled shafts translated and rotated at the pile-footing interface.Thus,the pile head did not behave in a fully fixed manner even though the drilled shaft reinforcement extends all the way up the abutment wall.Comparison of Movement at Both Abutments after Bridge Became IntegralTo evaluate the in-service movement of the abutment walls and shafts after the bridge became integral,the construction-induced movements are excluded by recalculating the movements using initial inclinometer readings that were read immediately after pouring the diaphragm and topping ͑on October 1,2004͒.After becoming integral,the abutment movements were quite sym-metrical ͑Fig.8͒except in the 2005/2006winter when the SE abutment moved more into the backfill than the NW abutment.The larger permanent deformation at the SE abutment may be caused by large hydrodynamic forces on the abutment due to the adverse stream meander ͑Fig.1͒during an exceptionally wet win-ter.In March 2006when Kaloko dam failed on the island of Kauai,the precipitation in Kahuku was 56cm ͓Fig.7͑b ͔͒.Lateral Earth PressureThe earth pressures at two elevations of the NW abutment,one in the GW fill and the other in the CLSM,are shown in Fig.3͑b ͒.The following observations are offered in chronological order:1.June 16,2004through August 26,2004—initially duringbackfilling,the earth pressure increased with backfill height in the GW fill and the CLSM.2.September 29through October 26,2004—after the bridgebecame integral on September 29,2004,the earth pressures continued to increase to a maximum value on October 26,2004at the NW abutment.This pressure spike coincided with placement of approach slab and additional backfill.The earth pressures in the GW fill at the same elevation on the SE abutment ͓Fig.3͑b ͔͒reached higher values than at the NW-2-1123456Displacement (mm)E l e v a t i o n (m )Fig.4.Deflected profile at the NW abutment and drilled shaft for several constructionevents-2-1123456Displacement (mm)E l e v a t i o n (m )Fig.5.Deflected profile at two air temperature extremities in a day10/JOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .abutment ͑Fig.9͒even though the backfill heights are iden-tical.This difference may be attributable to dissimilar compaction-induced stresses and/or to more softening of the backfill at the NW abutment due to the larger peak-to-peak thermal movements.3.October 26,2004through Winter 2005—during this period,the NW abutment moved towards the backfill by about 2mm due to stream loading with an insignificant change in the earth pressures.Around February 2005,the abutment re-versed its course by moving towards the stream due to creep and shrinkage of the superstructure and lower stream levels as the dry season approached.On February 21,2005,the contact pressure cell in the CLSM dropped to zero indicating separation between the wall and CLSM ͓Fig.3͑b ͔͒.4.May 16,2005through May 20,2005—in Fig.6͑b ͒,the earth pressures are not in phase with the daily thermal-induceddisplacements.When it is cool,the wall moves away from the backfill but the earth pressure increases and vice versa when it is hot.This is counterintuitive to classical earth pres-sure theories and involves a complex interaction between the backfill,abutment and approach slab.This behavior was fur-ther investigated using numerical analysis in a companion paper ͑Ooi et al.2010͒.5.Winter 2005through winter 2008—after the 2005winter,the abutments,as a result of concrete creep and shrinkage of the superstructure,moved towards the stream causing the earth pressure in the GW backfill to gradually relax ͓Figs.3͑b ͒and 9͔.In March 2008,the measured earth pressure at the NW abutment is less than the theoretical active earth pressure.At the SE abutment,the earth pressure is close to the theoretical active value.A possible explanation for the larger drop in earth pressure at the NW abutment is that more soil softening5/16/055/17/055/18/055/19/055/20/05DateD i s p l a c e m e n t (m m )A i r T e m p e r a t u r e (o C )(a)5/16/055/17/055/18/055/19/055/20/05DateL a t e r a l E a r t h P r e s s u r e (k P a )(b)Fig.6.͑a ͒Daily thermal-induced movement at the top inclinometer in the abutments;͑b ͒daily lateral pressure fluctuation at the NW abutmentJOURNAL OF BRIDGE ENGINEERING ©ASCE /JANUARY/FEBRUARY 2010/11D o w n l o a d e d f r o m a s c e l i b r a r y .o r g b y C H A N G 'A N U N I VE R S I T Y o n 01/07/16. C o p y r i g h t A S C E .F o r p e r s o n a l u s e o n l y ; a l l r i g h t s r e s e r v e d .。